I think the issue is that people want what will never be 100% to a laptop (seating/position wise) when talking about the Surface Pro lineup. The strides the Surface team have made with creating the SP3 with a Friction Hinge for multiple position use, is to be applauded. I also wonder, what else can be done? What some people want is a hard bottom on the Type Cover's, essentially creating a laptop/ultrabook. Wisely, MS has chosen to not offer yet ANOTHER Ultrabook, but a hybrid device that can bridge the gap between tablet and laptop. Its a unique proposition and one that everyone will NOT like. That's a given. Aside from creating a much, much better kickstand, MS has done as much as anyone could suggest as for "lapability". The next step and we mind as well create a traditional laptop/ultrabook. Something MS is moving away from to truly differentiate themselves from their OEM partners and the competition.
I've used the SP3 in my lap and it is a lot more stable to use in your lap. For those, that this doesn't work, that means its not an option for you (unfortunately). That doesn't mean that MS isn't doing this right or is wrong, it means that for you in particular, this device does not work. It's like complaining that a Porsche Cayenne Turbo can't return the same lap times as a 911 Turbo. If that is the case, proceed to purchase the item that better suits YOUR needs. Even Porsche themselves will market a Cayenne as the "911 of SUVs" a vehicle that can do it all. There are compromises (because there will always be those), but at this iteration you'd be pulling hairs, basically. If the SP3 is not "lapable" for you, then its not the design (the design will always be tablet-based first, with features helping transform the device into a lapable one), its the hard truth that this device won't work for your scenario. They all don't and never have. I would never complain about an iPad lacking the ability to do "real" work, because I would never buy one if my use case involved real work.
I think (in my opinion) we need to look at this SP3, understanding is idea of personal computing. Its not going to have a solid base, because that is literally another laptop. A 2 in 1 is being created by their OEM partners and is still nothing to get overly excited about. I personally feel, that there are no trade-offs with the SP3, just gains.